This invention relates generally to medical devices, systems, and methods, and more particularly to slit lamps used to illuminate and view an anterior segment of an eye, optionally during ophthalmic surgery.
Slit lamps are used in ophthalmic applications to view an anterior segment of an eye with a beam of light. The anterior segment of interest typically comprises a cornea, an iris, a sclera, an anterior lens capsule, a posterior lens capsule, and/or a lens nucleus. A beam of light can illuminate these tissues while an operator views an illuminated area through a magnification optic such as a microscope, or by direct examination.
The beam of light from a slit lamp can have a varying beam cross section. For example, in some instances the beam is desirably focused to form a narrow slit. Such a beam is desirable for examining layers of a cornea of an eye. In other instances, for example when viewing a large area of an eye, an operator adjusts the beam to have a wide beam cross section. Slit lamps often pass light through a slot aperture. In many instances, a variation in a size of a light beam is accomplished by mechanically changing a width across a slot aperture.
During LASIK refractive laser surgery a surgeon makes a corneal flap with a microkeratome. The surgeon is typically gloved and sterile during LASIK. After a flap is lifted from a corneal bed, the refractive laser treatment is performed on the stroma, and then the flap is laid back onto the stromal bed. The refractive laser surgeon will often take a patient from a laser system treatment chair to a commercial slit lamp. The surgeon evaluates quality and positioning of the LASIK incision and the resulting flap of tissue with the slit lamp. The beam from a slit lamp can be well suited for viewing debris under a LASIK flap and also for viewing wrinkles in a LASIK flap. Debris and flap wrinkles are appropriately treated and corrected upon detection with a slit lamp examination.
Sterile surgical covers and sterile lamp handles are known. However, these are not ideally suited for use during laser eye surgery and ophthalmic examinations. While ophthalmic slit lamps proposed to date appear to be generally safe for patient examinations during eye surgery, still further improvements would be desirable. In general, slit lamps having improved ease of use without compromising sterility would be desirable. For example, slit lamps permitting sterile evaluation of a patient while a patient remains in a chair of a laser refractive surgery system would be beneficial.